Such an inner rotor electric motor includes a stator having a plurality of tooth parts extending from an inner peripheral surface of an annular yoke part toward the center, and a rotor coaxially disposed at the center of the stator. The stator generally has a stator core made of a magnetic substance, and the stator core is insulatably covered with an insulator except for tooth surfaces.
With respect to an insulator, in a molded motor descend in Japanese Patent Application Publication No. 2010-148191, 24 insulator members per tooth part at 12 locations in Japanese Patent Application Publication No, 2010-148191) are fitted onto a stator core on either side thereof piece by piece and a coil is wound around each tooth part.
As found in Japanese Patent Application Publication No. 2010-166739, a stator core is wrapped with a winding, and thereafter an outer shell is formed to entirely cover a stator by resin one piece molding. A circuit board or the like is then assembled and brackets are provided to close openings, completing the stator.
In general, a bracket is formed in a so-called cup shape so as to cover an axial end face of a stator up to a part of an outer peripheral surface. The bracket is generally fixed to the stator with a part of its end deformed by crimping.
An engagement groove is provided on the outer peripheral surface of the stator as a receiver for the part deformed by crimping. A conventional engagement. groove has been formed by cutting a part of the outer peripheral surface after molding of an outer shell by milling or the like.
Cutting an engagement groove, however, causes shavings, which requires a post treatment.
An object of the invention, therefore, is to provide a molded motor that can provide size reduction as a whole while qualify of the motor is maintained.